There's been quite the controversy, especially on social media, since a Sulphur police officer shot and killed a 14-month-old dog while on duty last week. "Our employees and our police department, they'reMore >>

There's been quite the controversy, especially on social media, since a Sulphur police officer shot and killed a 14-month-old dog while on duty last week.More >>

The Sulphur police officer under investigation for fatally shooting a dog has a history of running into trouble on the job.More >>

The Sulphur police officer under investigation for fatally shooting a dog has a history of running into trouble on the job.More >>

SULPHUR, LA (KPLC) -

Brian Thierbach, the Sulphur police officer who fatally shot a dog last week, has resigned.

Sulphur Police Chief Lewis Coats said Thierbach submitted his resignation Wednesday, prior to final disciplinary action being taken against him.

Coats said that the joint investigation found that Thierbach "violated the Sulphur Police Department's Departmental Policy and Procedure regarding Use of Force and Personal Conduct and Behavior."

"In an effort to maintain transparency and to assure no appearance of impropriety, (we) requested the assistance of the Calcasieu Parish Sheriff's Office in conducting an internal affairs investigation of Officer Thierbach's actions regarding the shooting of a dog on April 28, 2014," Coats said in a news release.

"I am a dog lover and I am deeply saddened by this incident," Coats said. "I realize there is nothing I can say that would take away the hurt this incident has caused Mr. Brandon Carpenter. The actions of Officer Thierbach did not represent what I expect from the officers of the Sulphur Police Department. Those of us who serve as law enforcement officers do so with the responsibility of serving and protecting the community as professionals. The resignation of Officer Thierbach was accepted so that the officers and community can heal and move forward."

Coats said the Calcasieu Parish Sheriff's Office is conducting a criminal investigation into the shooting.